1. Field of the Invention
The present invention relates to a wireless IC device, and more specifically to a wireless IC device having a wireless IC chip used in an RFID (Radio Frequency Identification) system, and an electronic apparatus including the wireless IC device.
2. Description of the Related Art
In recent years, an RFID system has been developed as an item management system, in which communication is performed in a non-contact manner between a reader/writer that generates an induction field, and an IC chip (also referred to as the IC tag or wireless IC chip) storing predetermined information and attached to an item, a container, or the like to thereby transmit information.
PCT Japanese Translation Patent Publication No. 11-515094 describes an RFID tag including an IC chip and an antenna formed within a printed wiring circuit board. In this RFID tag, the antenna within the printed wiring circuit board and the IC chip mounted on the principal surface of that board are connected to each other in an electrically conductive state. Miniaturization of the RFID tag is achieved by arranging the antenna within the printed wiring circuit board.
However, since this RFID tag includes a dedicated antenna, an antenna fabrication process is required, leading to an increase in cost. Further, an installation space for the antenna is also required, resulting in an increase in size. In particular, if the antenna is formed in a substantially meandering shape as depicted in FIG. 2 of PCT Japanese Translation Patent Publication No. 11-515094, it is necessary to machine inner electrodes across a plurality of layers, which elongates the fabrication process. Further, a matching part for matching the impedance between the IC chip and the antenna is required. In this case, if the matching part is provided at the connecting part between the antenna and the IC chip, the antenna is enlarged, and if the IC chip is changed, it is necessary to change the shape of the antenna or the like as well.